Attempting to fix an eBay Purchased Killer Instinct Board

[RealMFnG]

Came in today and looks to be pretty darn clean. The CPU was removed from it which leads me to suspect the CPU was harvested to repair another board. Which means there is more wrong with this board than just a missing CPU. Was going to wash it with Simple Green, but looks to be pretty darn clean already and in really good shape otherwise.

Should I even plug this thing in?

 

[RealMFnG]

Found my spare CPU's for Killer Instinct!!!

Checked the PCB SMD solder joints under magnification and see some solder bridges. Will have to clean that up before getting going. The package pitch is very small. I dunno if it makes sense to hand solder this. What do you guys think? Shall we go with solder paste and SMD rework or hand solder?

 

[Hammy]

1 in 5 success rate on *complete* KI's pcb's.
In this condition it's a 1 in 30 shot so don't go too mad on buying parts / spending time , especially if there's n00b damage on the pads / lines.

My only advice after fitting the chip is microscope, microscope , microscope , and microscope once again before plugging in

 

[RealMFnG]

Thanks @Hammy. I was lucky and was able to pick up these CPU's a while back on the cheap. It is the most I plan on investing into this pick-up.

What do you think of this endoscope in place of a microscope?

 

[Hammy]

Yes, that's similar to what i use

There's a few "china factory" making the exact same thing and some are lower quality than others.
If the one you get feels like it's gonna fall apart any second and the zoom button does nothing you got the crap type - be warned

As for the soldering, avoid hot air as much as possible - go for hand soldering but spend time on alignment first.
Keep the CPU away until all solder is GONE from the pads, as alignment on unclean surface (with solder lying around) will bend the pins.

 

[channelmaniac]

I have to ask... WHERE in the world did you find those CPUs? They are pretty much unobtanium.

 

[ekorz]

@channelmaniac iirc UTSource listed some a couple years ago, but they all got bought up when that news hit the forums. I’m not sure who the actual supplier was though everyone purchased from utsource I think